JP4563353B2 - Engine vibration and noise reduction method and apparatus - Google Patents

Description

  The present invention is applied to a diesel engine or the like equipped with a common rail electronically controlled fuel control device, and an engine having a fuel control device capable of changing a fuel injection mode such as fuel injection timing and fuel injection amount to suppress vibration of the engine. The present invention relates to a vibration and noise reduction method and apparatus therefor.

2. Description of the Related Art In recent years, diesel engines, particularly automobile diesel engines such as automobiles, have been promoted to adopt common rail electronically controlled fuel control devices from the viewpoints of both exhaust gas regulations and fuel consumption rate improvements.
Electronic control fuel control devices such as common rail electronic control fuel control devices and electromagnetic control unit injectors are used for pre-injection before and after main injection, fuel injection timing such as fuel injection timing in these injection modes, fuel injection amount, etc. By changing the fuel injection mode freely, it is possible to improve both the exhaust gas performance of the engine and the fuel consumption rate.
However, in the diesel engine, if the setting range of the fuel injection condition is expanded to improve both the exhaust gas performance and the fuel consumption rate by using the electronic control fuel control device as described above, the vibration of the engine (Airframe vibration and torsional vibration) and noise are also greatly affected, and when fuel injection conditions are set so that both engine exhaust gas performance and fuel consumption rate are optimal, the engine vibration or noise is large under such fuel injection conditions. Can be. Reduction of engine vibration and noise is also a major issue for diesel engines.

For this reason, conventionally, the engine with the fuel injection conditions where both the engine exhaust gas performance and the fuel consumption rate as described above are set to the best is operated and the engine vibration and noise are measured. Matching that optimizes both engine performance such as fuel consumption rate and engine vibration and noise has been obtained through experimental operation using actual engine.
FIG. 6 shows measurement results of engine performance and engine noise by an actual machine test performed on a diesel engine equipped with a common rail electronically controlled fuel control device. 6A shows measured values of the in-cylinder pressure and the fuel injection mode, FIG. 6B shows measured values of the heat receiving rate in the cylinder, and FIG. 6C shows measured values of engine airframe noise. As shown in FIG. 6A, this diesel engine is a multi-stage injection mode engine that performs pre-injection of pre-injection and post-injection before and after the main injection of fuel.

Patent Document 1 (Japanese Patent Application Laid-Open No. 2005-264810 discloses a change in the injection timing of main injection and pre-injection in a diesel engine in which the fuel injection mode is a multi-stage injection mode in which pre-injection is performed before main injection. Thus, it is disclosed to obtain an optimal injection timing capable of reducing engine vibration and engine noise.
JP 2005-264810 A

As described above, in a diesel engine equipped with an electronically controlled fuel control device, conventionally, matching is performed so that engine performance such as engine exhaust gas performance and fuel consumption rate and engine vibration and noise are best. However, in order to obtain a match between the required engine performance and engine vibration and noise, it is necessary to repeatedly perform experiments with different fuel injection conditions and engine vibration factors. was there.
For this reason, this conventional technique solves the problem that a large amount of experiment man-hours and experiment costs are required for an experimental operation using an actual engine to obtain matching between engine performance conditions such as fuel injection conditions and engine vibration and noise. Have problems to be solved.
Further, Patent Document 1 discloses that the optimal injection timing that can reduce the engine vibration and the engine noise is obtained by changing the injection timings of the main injection and the pre-injection. Is not mentioned at all.

  In view of the problems of the prior art, the present invention is capable of optimal matching between engine performance conditions such as fuel injection conditions and engine vibration and noise with less man-hours and low cost without performing an experimental operation with an actual engine. An object of the present invention is to provide an engine vibration and noise reduction method and apparatus that can be obtained.

The present invention achieves such an object, and is an engine vibration reduction method for suppressing engine vibration comprising a fuel control device capable of changing a fuel injection mode including a fuel injection timing and a fuel injection amount. A plurality of types of engine vibration points including the mass of the vibration element made up of components involved in the vibration and the spring constant are set, and the corresponding in-cylinder pressure change is estimated from the fuel injection mode. The procedure for calculating the vibration force is performed for a plurality of types of fuel injection modes, and the engine vibration is calculated based on the plurality of types of excitation forces and the plurality of types of engine vibration guidelines, and the engine vibration falls below an allowable value. Extracting a combination of the engine vibration guideline and the fuel injection mode, and applying the combination to the engine. Characterized in that (claim 1).

Further, an invention of an apparatus for carrying out the method invention is an engine vibration reduction system configured to suppress vibration of an engine having a fuel control device capable of changing a fuel injection mode including a fuel injection timing and a fuel injection amount. In the apparatus, an excitation force calculation means for estimating an in-cylinder pressure change from a plurality of the fuel injection modes and calculating an excitation force based on the in-cylinder pressure change, and a vibration element comprising components involved in engine vibration Engine vibration summary setting means in which a plurality of types of engine vibration features including mass and spring constant are set, and a plurality of vibration forces calculated by the vibration force calculation means and a plurality of types of engine vibration features. Engine vibration calculating means for calculating engine vibration, engine vibration allowable value setting means for setting the engine vibration allowable value, and engine vibration calculation The engine vibration such that the calculated engine vibration is equal to or less than the allowable value of the engine vibration by comparing a plurality of calculated engine vibration values by the means with the allowable engine vibration value set in the allowable engine vibration value setting means. The present invention is characterized in that a controller including minimum vibration item extracting means for extracting a combination of the item and the fuel injection mode is provided (claim 3 ).

According to this invention, the controller changes a plurality of types of engine vibration points such as the mass of engine components such as a crankcase, the spring constant and vibration damping coefficient of the engine support system, and the fuel injection method, fuel injection timing, cylinder pressure changes and vibratory force calculated fuel injection mode or these fuel injection quantity, etc. by a plurality of types changes, each of the plurality of combinations of the plurality of types of a plurality of types and a fuel injection mode of the engine vibration curriculum The engine vibration is calculated with respect to the engine vibration calculated value by the plurality of combinations, and the combination of the engine vibration key and the fuel injection mode in the engine vibration calculated value that is equal to or less than the allowable value of the engine vibration of the target engine. It can be extracted and applied to the engine.

  Thereby, the engine such as the mass of the engine component, the spring constant of the engine support system, and the vibration damping coefficient such that the engine vibration of the target engine is less than the allowable value by the simulation calculation and control on the computer (controller). Combinations of vibration points and fuel injection modes, fuel injection timing, fuel injection timing, and other fuel injection modes that match them, that is, engine vibration points and fuel injection conditions that make the engine vibration of the engine less than the allowable value It is possible to extract the optimum combination with the engine performance conditions such as the above, and as in the prior art, the experimental operation by the actual engine to obtain the optimum matching between the engine performance conditions such as the fuel injection conditions and the engine vibration Eliminates the need for experiment man-hours and experiment costs associated with such experimental operation. Kill.

Further, the present invention is an engine noise reduction method for suppressing engine noise provided with a fuel control device capable of changing the fuel injection mode similar to the above, and a vibration element comprising parts involved in vibration of the engine A procedure for calculating a plurality of types of engine vibration points including the mass and spring constant of the engine, estimating a corresponding in-cylinder pressure change from the fuel injection mode, and calculating an excitation force based on the in-cylinder pressure change The engine vibration is calculated based on the plurality of types of excitation force and the plurality of types of engine vibration, and each engine vibration is handled based on the calculated values of the plurality of types of engine vibration. Each engine noise is calculated, and a combination of the engine vibration guideline and the fuel injection mode that makes the engine noise less than the allowable value is extracted, and the combination is extracted. And wherein applying the Align the engine (claim 2).

Further, the invention of an apparatus for carrying out the method invention includes an excitation force calculating means for estimating an in-cylinder pressure change from a plurality of the fuel injection modes and calculating an excitation force based on the in-cylinder pressure change, and an engine Engine vibration outline setting means in which a plurality of types of engine vibration outlines including the mass of the vibration element composed of components involved in vibration and the spring constant are set; and the plurality of excitation forces calculated by the excitation force calculation means; Engine vibration calculating means for calculating engine vibration based on a plurality of types of engine vibration parameters, and engine noise calculating means for calculating engine noise corresponding to each engine vibration based on the calculated values of the plurality of types of engine vibration, respectively. Engine noise tolerance setting means in which the engine noise tolerance is set; and a plurality of engine noise calculation values by the engine noise calculation means; The engine vibration guideline and the fuel injection mode are such that the calculated engine noise value is less than the allowable engine noise value by comparing with the allowable engine noise value set in the engine noise allowable value setting means. An engine noise reduction device comprising a controller comprising minimum vibration feature extraction means for extracting combinations (claim 4 ).

According to this invention, the controller calculates engine vibration and engine noise corresponding to engine vibration for each of a plurality of combinations of a plurality of types of the engine vibration items and a plurality of types of fuel injection modes, and the plurality of combinations It is possible to extract a combination of the engine vibration point and the fuel injection mode in the calculated engine noise value that is equal to or lower than the allowable engine noise value of the target engine from the calculated engine noise value of the target engine and apply it to the engine It becomes.
Thereby, the engine such as the mass of the engine component, the spring constant of the engine support system, and the vibration damping coefficient so that the engine noise of the target engine is less than the allowable value by the simulation calculation and control on the computer (controller). A combination of vibration points and a fuel injection mode, fuel injection timing, fuel injection amount, and other fuel injection modes that match this, that is, engine vibration points and fuel injection conditions that make the engine noise of the engine less than the allowable value The optimum combination with the engine performance conditions such as the fuel injection conditions can be extracted, and the experimental operation by the actual engine for obtaining the optimum matching between the engine performance conditions such as the fuel injection conditions and the engine noise as in the prior art becomes unnecessary. Therefore, it is possible to avoid the generation of experimental man-hours and experimental costs associated with such experimental operation.

  According to the present invention, the mass of the engine component, the spring constant of the engine support system, and the engine constant so that the engine vibration and engine noise of the target engine are less than the allowable values by the simulation calculation and control on the computer (controller). Combinations of engine vibration requirements such as vibration damping coefficient and fuel injection mode, fuel injection timing, fuel injection amount and other fuel injection modes that match this, that is, the engine vibration and engine noise of the engine are below the allowable values The optimal combination of engine performance conditions such as fuel injection conditions and engine performance conditions can be extracted, and as in the prior art, optimal matching between engine performance conditions such as fuel injection conditions and engine vibration and engine noise. This eliminates the need for experimental operation with the actual engine to obtain The occurrence of the experimental man-hours and experimental costs associated with can be avoided.

  Hereinafter, the present invention will be described in detail with reference to the embodiments shown in the drawings. However, the dimensions, materials, shapes, relative arrangements, and the like of the component parts described in this example are not intended to limit the scope of the present invention only to specific examples unless otherwise specified. Only.

1 is an overall configuration diagram of a vibration and noise reduction device for a diesel engine according to first to third embodiments of the present invention.
In FIG. 1, 100 is an engine, 101 is a cylinder of the engine 100 (in this case, an in-line 6-cylinder engine), 102 is a fuel injection valve for injecting fuel into each cylinder 101, 105 is a common rail, and 107 is fuel supply A pipe 106 is a fuel pump that pressurizes the fuel in the fuel supply pipe 107 to a high pressure and pumps the fuel into the common rail 105.
Reference numeral 104 denotes an injection pipe that connects the common rail 105 and each fuel injection valve 102. Reference numeral 103 denotes an electromagnetic valve that is provided in the injection pipe 104 and supplies and shuts off high-pressure fuel to the fuel injection valve 102. 110 is a fuel control device that controls the opening and closing of each electromagnetic valve 103. The fuel injection mode such as the fuel injection timing and fuel injection amount of the engine 100 is set, and the opening and closing of each electromagnetic valve 103 is controlled according to the fuel injection mode. To do.
Reference numeral 1 denotes a controller which is connected to the fuel control device 110 and performs calculation and control as will be described later.

FIG. 2 is a control block diagram of a vibration reduction device for a diesel engine in the first embodiment of the present invention, and FIG. 3 is a control flowchart in the first embodiment.
2 and 3, reference numeral 20 denotes a fuel injection mode setting unit in the fuel control device 110, which is an engine fuel injection system (pre-injection, main injection, and post-injection three-stage injection as shown in FIG. 6A). A plurality of types of fuel injection modes such as a fuel injection timing, a fuel injection timing, and a fuel injection amount are set stepwise or in a matrix.
Reference numeral 11 denotes a fuel injection mode extraction unit that extracts a plurality of types of fuel injection modes within a range necessary for calculation of engine vibration and engine noise, which will be described later, from the fuel injection mode set in the fuel injection mode setting unit 20. And input to the in-cylinder pressure calculation unit 29 (step (2) in FIG. 3). The in-cylinder pressure calculation unit 29 calculates a heat receiving rate (heat generation rate) as shown in FIG. 6B from the fuel injection mode, and based on the heat receiving rate, as shown in FIG. 6A. An in-cylinder pressure change is calculated for each of the plurality of types of fuel injection modes and input to the excitation force calculation unit 12 (step (3) in FIG. 3). The excitation force calculation unit 12 calculates an excitation force of engine vibration based on the calculated value of the in-cylinder pressure change for each of the plurality of types of fuel injection modes, and inputs the calculated vibration force to each unit vibration calculation unit 14 (FIG. 3 step (4)).

Reference numeral 13 denotes an engine vibration element setting unit, in which a plurality of types of engine vibration items such as the mass of engine components such as a crankcase, the spring constant and vibration damping coefficient of the engine support system are set stepwise or in a matrix ( Step (1) in FIG.
In each part vibration calculation unit 14, a plurality of types of engine vibration items set in the engine vibration element setting unit and a vibration force for a plurality of types of fuel injection modes input from the vibration force calculation unit 12. The calculated engine vibration is calculated for each of a plurality of combinations of the engine vibration summary and the vibration generating force for the fuel injection mode, and input to the vibration comparison / determination unit 16.

Reference numeral 15 denotes an allowable vibration value setting unit in which an allowable value of engine vibration of the target engine is set (step (5) in FIG. 3). In each part vibration comparison and determination unit 16, the calculated value of the engine vibration calculated by the respective part vibration calculation unit 14 and the allowable value of the engine vibration of the target engine 100 set in the allowable vibration value setting unit 15 (Steps (6, 7 in FIG. 3)), a combination of the engine vibration point and the fuel injection mode is extracted so that the calculated value of the engine vibration is not more than an allowable value.
When there are a plurality of combinations, the fuel injection mode selection unit 17 selects a combination of fuel injection modes that provides the best engine performance such as engine exhaust gas performance and fuel consumption rate with respect to the engine vibration point of the target engine. (Step (8) in FIG. 3).

  According to the first embodiment, the controller 1 allows a plurality of types of engine vibration points such as the mass of engine components such as a crankcase, the spring constant and vibration damping coefficient of the engine support system, the fuel injection method, and the fuel injection timing. The fuel injection mode such as the fuel injection amount, the in-cylinder pressure change and the excitation force calculated from the fuel injection mode are respectively changed, and the plurality of types of engine vibration points and the plurality of types of fuel injection modes are changed. Engine vibration is calculated for each of a plurality of combinations, and the engine vibration calculation value in the engine vibration calculation value such that the engine vibration calculation value of the plurality of combinations is equal to or less than the allowable value of the engine vibration of the target engine 100. And a combination of fuel injection modes can be extracted and applied to the engine 100.

  Accordingly, the mass of the engine component, the spring constant of the engine support system, the vibration damping coefficient, etc., such that the engine vibration of the target engine 100 is less than the allowable value by the simulation calculation and control on the computer (controller). A combination of the engine vibration summary and a fuel injection mode, a fuel injection timing, a fuel injection amount, and other fuel injection modes corresponding thereto, that is, an engine vibration summary and fuel that causes the engine vibration of the engine 100 to be below an allowable value. The optimum combination with the engine performance conditions such as the injection conditions can be extracted. As in the prior art, the experimental operation by the actual engine for obtaining the optimum matching between the engine performance conditions such as the fuel injection conditions and the engine vibration can be performed. This eliminates the need for experiment man-hours and experiment costs associated with such experimental operation. That.

FIG. 4 is a control block diagram of a vibration reducing device for a diesel engine in the second embodiment of the present invention.
In this embodiment, the engine noise is calculated using the calculated value of the engine vibration in the first embodiment, and the operations up to the vibration calculation section 14 in FIG. 4 are the same as those in the first embodiment shown in FIG. It is the same.
In FIG. 4, in each part vibration calculation unit 14, a plurality of types of engine vibration elements set in the engine vibration element setting unit and a plurality of types of fuel injection modes input from the excitation force calculation unit 12 are described. The engine vibration is calculated for each of a plurality of combinations of the engine vibration element and the vibration generating force for the fuel injection mode using the calculated value of the vibration generating force, and is input to the noise calculating unit 18. In each part noise calculation part 18, the noise of each part of the engine for each of a plurality of combinations of the engine vibration points from the part vibration calculation part 14 and the vibration generating force for the fuel injection mode based on the engine vibration calculation value. Is calculated and input to the noise comparison / determination unit 19.

Reference numeral 21 denotes a noise allowable value setting unit in which an allowable value of engine noise of the target engine 100 is set. The noise comparison / determination unit 19 calculates the calculated engine noise value calculated by the noise calculation unit 18 and the allowable engine noise value of the target engine 100 set in the allowable noise value setting unit 21. And a combination of the engine vibration point and the fuel injection mode so that the calculated value of the engine noise is less than or equal to an allowable value is extracted.
When there are a plurality of combinations, the fuel injection mode selection unit 17 selects a combination of fuel injection modes that provides the best engine performance such as engine exhaust gas performance and fuel consumption rate with respect to the engine vibration point of the target engine. .

According to the second embodiment, the controller 1 calculates the engine vibration and the engine noise corresponding to the engine vibration for each of the plurality of combinations of the plurality of types of engine vibration points and the plurality of types of fuel injection modes, From the engine noise calculation values of the plurality of combinations, a combination of the engine vibration point and the fuel injection mode in the engine noise calculation values that are less than or equal to the allowable engine noise value of the target engine 100 is extracted and stored in the engine. It becomes possible to apply.
Thereby, the mass of the engine component, the spring constant of the engine support system, the vibration damping coefficient, etc., such that the engine noise of the target engine 100 is less than the allowable value by the simulation calculation and control on the computer (controller 1). A combination of a fuel injection method, a fuel injection method, a fuel injection timing, a fuel injection amount, and other fuel injection modes corresponding to the engine vibration guideline, that is, an engine vibration guideline such that the engine noise of the engine 100 is less than an allowable value. The optimum combination with engine performance conditions such as fuel injection conditions can be extracted, and as in the prior art, an experimental operation with an actual engine to obtain an optimal matching between engine performance conditions such as fuel injection conditions and engine noise Eliminates the need for experiment man-hours and experiment costs associated with such experimental operation. Kill.

FIG. 5 is a control block diagram of the in-cylinder pressure estimating device for the diesel engine in the third embodiment of the present invention.
In the third embodiment, the vibration of the engine 100 is detected, the engine vibration item including the mass and the spring constant of the vibration element composed of the components involved in the vibration of the vibration detection engine 100, and the detected value of the engine vibration, Is used to calculate the vibration force of the engine vibration, and the in-cylinder pressure change of the engine 100 is estimated using the set value of the relationship between the vibration force of the engine 100 and the in-cylinder pressure.

That is, in FIG. 5, each part vibration detecting means 2 detects engine vibrations of parts of the engine, preferably engine vibrations at a part where vibrations due to in-cylinder pressure are noticeable, and this detected value is detected by the in-cylinder pressure estimating means 3. Input to the vibration force calculator 31.
Reference numeral 32 denotes an engine vibration element setting unit in which engine vibration items such as the mass of engine components such as a crankcase, the spring constant of the engine support system, and the vibration damping coefficient are set for the vibration detection engine 100.
The excitation force calculation unit 31 calculates the excitation force of the engine vibration from the vibration detection value and the vibration point of the engine 100 set in the engine vibration element setting unit 32, and the in-cylinder pressure calculation unit 34 input.

  Reference numeral 33 denotes an excitation force / in-cylinder pressure setting unit in which a relationship between the excitation force and the in-cylinder pressure in the engine 100 is set. The in-cylinder pressure calculation unit 34 extracts the value of the in-cylinder pressure corresponding to the excitation force of the engine vibration calculated by the excitation force calculation unit 31 from the excitation force / in-cylinder pressure setting unit. The estimated value of in-cylinder pressure is used.

  According to the third embodiment, the vibration of the engine 100 is detected, and the computer (in-cylinder pressure estimating means 3) calculates the vibration excitation force from the vibration detection value and the vibration point of the engine 100, By estimating the in-cylinder pressure change of the engine 100 using the set value of the relationship between the vibration generating force and the in-cylinder pressure, for example, a cylinder such as an upper part of the cylinder block is provided when there is no measuring means for the in-cylinder pressure change. In-cylinder pressure changes can be easily estimated by detecting engine vibrations where vibration due to internal pressure appears prominently, and by understanding the correlation between such engine vibrations and in-cylinder pressure changes, engine vibrations can be estimated. It is possible to easily estimate the in-cylinder pressure change and the fuel injection mode that can suppress the above.

  According to the present invention, it is possible to obtain an optimal matching between engine performance conditions such as fuel injection conditions and engine vibration and noise with less man-hours and low cost without performing an experimental operation with an actual engine. An engine vibration and noise reduction method and apparatus can be provided.

It is a whole block diagram of the vibration and noise reduction apparatus of the diesel engine which concerns on the 1st-3rd Example of this invention. It is a control block diagram of the vibration reduction apparatus of the diesel engine in 1st Example of this invention. It is a control flowchart in the first embodiment. It is a control block diagram of the vibration reduction apparatus of the diesel engine in 2nd Example of this invention. It is a control block diagram of the cylinder pressure estimation apparatus of the diesel engine in 3rd Example of this invention. Shows engine performance and engine noise measurement results from an actual machine test conducted on a diesel engine equipped with a common rail electronically controlled fuel control system. (A) shows measured values of in-cylinder pressure and fuel injection mode. , (C) shows the measured value of engine body noise.

DESCRIPTION OF SYMBOLS 1 Controller 2 Each part vibration detection means 3 In-cylinder pressure estimation means 100 Engine 101 Cylinder 102 Fuel injection valve 103 Electromagnetic valve 104 Injection pipe 105 Common rail 106 Fuel pump 110 Fuel control apparatus

Claims (4)

An engine vibration reducing method for suppressing engine vibration comprising a fuel control device capable of changing a fuel injection mode including a fuel injection timing and a fuel injection amount ,
A plurality of engine vibration points including the mass of a vibration element composed of parts involved in the engine vibration and a spring constant are set, a corresponding in-cylinder pressure change is estimated from the fuel injection mode, and the in-cylinder pressure change is determined. The procedure for calculating the excitation force is performed for a plurality of types of fuel injection modes, and the engine vibration is calculated based on the plurality of types of excitation force and the plurality of types of engine vibration guidelines. A method of reducing engine vibration, comprising: extracting a combination of the engine vibration summary and the fuel injection mode as described below and applying the combination to the engine. An engine noise reduction method for suppressing engine noise comprising a fuel control device capable of changing a fuel injection mode including a fuel injection timing and a fuel injection amount,
A plurality of engine vibration points including the mass of a vibration element composed of parts involved in the engine vibration and a spring constant are set, a corresponding in-cylinder pressure change is estimated from the fuel injection mode, and the in-cylinder pressure change is determined. The procedure for calculating the excitation force based on the plurality of types of fuel injection modes is performed, and the engine vibration is calculated based on the plurality of types of excitation force and the plurality of types of the engine vibration points, and the plurality of types of the engine vibrations are calculated. Based on the calculated value, engine noise corresponding to each engine vibration is calculated, and a combination of the engine vibration guideline and the fuel injection mode is extracted so that the engine noise is less than or equal to an allowable value. An engine noise reduction method characterized by applying to the engine . An engine vibration reduction device configured to suppress vibrations of an engine having a fuel control device capable of changing a fuel injection mode including a fuel injection timing and a fuel injection amount. Excitation force calculation means for estimating the change and calculating the excitation force based on the in-cylinder pressure change, and multiple types of engine vibration parameters including the mass of the vibration elements and spring constants composed of parts involved in engine vibration A set engine vibration item setting means;
Engine vibration calculation means for calculating engine vibration based on a plurality of vibration forces calculated by the vibration force calculation means and a plurality of types of engine vibration parameters, and engine vibration in which an allowable value of the engine vibration is set The engine vibration calculated value is obtained by comparing the engine vibration calculated values obtained by the allowable value setting means, the engine vibration calculating means and the engine vibration allowable values set by the engine vibration allowable value setting means. An engine vibration reducing apparatus comprising a controller comprising minimum vibration point extracting means for extracting a combination of the engine vibration point and the fuel injection mode that is less than an allowable value . An engine noise reduction device configured to suppress engine noise having a fuel control device capable of changing a fuel injection mode including a fuel injection timing and a fuel injection amount. Excitation force calculation means for estimating the change and calculating the excitation force based on the in-cylinder pressure change, and multiple types of engine vibration parameters including the mass of the vibration elements and spring constants composed of parts involved in engine vibration A set engine vibration item setting means;
Engine vibration calculation means for calculating engine vibration based on the plurality of vibration forces calculated by the vibration force calculation means and the plurality of types of engine vibration parameters, respectively, Engine noise calculation means for calculating engine noise corresponding to engine vibration, engine noise tolerance setting means in which the engine noise tolerance is set,
The engine noise calculation value is equal to or less than the engine noise allowable value by comparing a plurality of engine noise calculated values by the engine noise calculating unit with the engine noise allowable value set in the engine noise allowable value setting unit. An engine noise reduction device comprising a controller comprising minimum vibration point extraction means for extracting a combination of the engine vibration point and the fuel injection mode .

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